def add(x, y):
    return x + y


class TestAddFun():
    def test01(self):
        res = add(10, 20)
        assert 30 == res

    def test02(self):
        res = add(100, 200)
        assert 300 == res

    def test03(self):
        res = add(1000, 2000)
        assert 3000 == res

    def test04(self):
        res = add(10000, 20000)
        assert 30000 == res
